One of those tweaks is the capability to disable notifications for a particular app. This will come in handy if you have an app that's overloading you with notifications, with no setting in the app to disable them. But now you can do it at the OS level in Android 4.1.

You may notice there is a new option in the App Info screen that allows you to turn off notifications for an app.

You can get to the App Info screen by long-pressing on a notification, or going into Settings > Apps and then selecting the app for which you want to disable notifications. Tap on the check mark box next to Show Notifications and accept the warning. Going forward, you'll no longer receive notifications for that specific app.

If you change your mind, enter Settings > Apps again and recheck the box for the app.

The video below will walk you through both methods and give you a better idea of how it all looks.